Dont need to do that, the card drivers only load at the windows screen, it would not cause a boot issue. One long beep means a gpu issue so like said check the card is seated propper in the pci-e slot and double check your power to the card. You really do need to reset the cmos every time you put a new card it too. If that dont work try another pci-e lane if you have 2 or more.

Exactly it should not be an issue with the old drivers. OP said he/she removed them and the computer would still not post. Also the old drivers can be removed in safe mode as it uses default drivers. So that rules the driver issue out in my mind.

Call ASUS and see if they know why that card won't work in your board. Was the 3870 from Dell instead of another vendor like Shappire/ASUS? I wonder if they made it so that card would only with with those boards?

Call ASUS and see if they know why that card won't work in your board. Was the 3870 from Dell instead of another vendor like Shappire/ASUS? I wonder if they made it so that card would only with with those boards?